The two were designed for APS-C format cameras and adapted to m4/3. So the 30mm is into the no man's land between normal and portrait and the 19mm isn't quite the street wide they would be on a APS-C sensor. Robert Cicala at LensRentals notes that "the new Sigma lenses stand out as superb compared to other NEX lenses, but are just another good prime lens on the m/4/3 system." In terms of how LensRental's Imatest resolution test rated them for average sharpness across the frame (lp/img hgt), here's how they hold up at f/2.8: